Sd = 1-7 LB = - D UB = 24. u = 23:1 0 = 1.7 13 - Suppose the mass of nickel in a nickel (minted after 1982) is N(23.1, 1.7) mg. LB = = 00 a) What percent of post-1982 nickels contain less than 24 mg of nickel (5 pts)? UB = 24 M = 23 . 1 0 = 1.7 b) If twenty post-1982 nickels are melted down, what is the probability they will yield at least 450 mg of nickel (5 pts)? n = 20 I = 450 = 22:5 LB = 22.5 20 M = 23 . 1 c) What percent of post-1982 nickels contain greater than 23 mg of nickel (5 pts)? 23. 7 V20 13 - (5) 60% of teenagers eat breakfast on school days. a) What is the complement of this event? b) What is the probability of this event? c) If 4 teenagers are selected at random, what is P(teenager eats breakfast on school days)? d) If 4 teenagers are selected at random, what is the probability that none eat breakfast on school days? e) If 4 teenagers are selected at random, what is the probability that at least on of them eats breakfast on school days? 14- The random variable X, representing the number of items sold in a week, has the following probability distribution: X 0 1 2 3 4 5 6 P(X) 0.1 0.2 0.4 0.15 0.05 0.05 0.05 a) What is the probability that in a given week there will be at most 4 items sold? 6 ) By the fourth day of a particular week, 3 items have already been sold. What is the probability there will be less than a total of 5 items sold during that week? c) What is the expected number of items sold in a week